The work is a continuation of earlier studies on the stability of proteins and the factors that affect their unfolding and refolding reactions. Central to the studies is the use of mutants of the protein T4 lysozyme that permit us to assay the effects of individual amino acids on the equilibrium and rates of the folding reaction. We also perform variations of temperature, pH, ionic strength, and the concentration of denaturants and other substances so that we can develop complete thermodynamic and kinetic models. Our program is directed toward four aspects of this problem: 1. The study of low temperature unfolding. We have completed a study on one mutant, C3T54, and wish to look at the effects of mutations on the stability and kinetics of the unfolding and refolding reaction. 2. Studies of the interaction of proteins with water and denaturing agents. 3. Studies of the limited proteolysis of temperature-sensitive and other mutants in order to evaluate the local instabilities produced by mutations. 4. The continuation of our collaboration on families of mutants that have been generated in the laboratories of B. Matthews and F. Dahlquist. Their groups do the structural, dynamic and genetic studies while we specialize in thermodynamics, spectroscopy and kinetics.

Agency
National Institute of Health (NIH)
Institute
National Institute of General Medical Sciences (NIGMS)
Type
Research Project (R01)
Project #
5R01GM020195-32
Application #
3269932
Study Section
Biophysics and Biophysical Chemistry A Study Section (BBCA)
Project Start
1978-04-01
Project End
1993-03-31
Budget Start
1989-04-01
Budget End
1990-03-31
Support Year
32
Fiscal Year
1989
Total Cost
Indirect Cost
Name
University of Oregon
Department
Type
Organized Research Units
DUNS #
948117312
City
Eugene
State
OR
Country
United States
Zip Code
97403
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Daopin, S; Alber, T; Baase, W A et al. (1991) Structural and thermodynamic analysis of the packing of two alpha-helices in bacteriophage T4 lysozyme. J Mol Biol 221:647-67
Dao-pin, S; Soderlind, E; Baase, W A et al. (1991) Cumulative site-directed charge-change replacements in bacteriophage T4 lysozyme suggest that long-range electrostatic interactions contribute little to protein stability. J Mol Biol 221:873-87

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